/*-------------------------------------------------------------------------
*
* pgtime.h
* PostgreSQL internal timezone library
*
* Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
*
* IDENTIFICATION
* src/include/pgtime.h
*
*-------------------------------------------------------------------------
*/
#ifndef _PGTIME_H
#define _PGTIME_H
/*
* The API of this library is generally similar to the corresponding
* C library functions, except that we use pg_time_t which (we hope) is
* 64 bits wide, and which is most definitely signed not unsigned.
*/
typedef int64 pg_time_t;
/*
* Data structure representing a broken-down timestamp.
*
* CAUTION: the IANA timezone library (src/timezone/) follows the POSIX
* convention that tm_mon counts from 0 and tm_year is relative to 1900.
* However, Postgres' datetime functions generally treat tm_mon as counting
* from 1 and tm_year as relative to 1 BC. Be sure to make the appropriate
* adjustments when moving from one code domain to the other.
*/
struct pg_tm
{
int tm_sec;
int tm_min;
int tm_hour;
int tm_mday;
int tm_mon; /* see above */
int tm_year; /* see above */
int tm_wday;
int tm_yday;
int tm_isdst;
long int tm_gmtoff;
const char *tm_zone;
};
/* These structs are opaque outside the timezone library */
typedef struct pg_tz pg_tz;
typedef struct pg_tzenum pg_tzenum;
/* Maximum length of a timezone name (not including trailing null) */
#define TZ_STRLEN_MAX 255
/* these functions are in localtime.c */
extern struct pg_tm *pg_localtime(const pg_time_t *timep, const pg_tz *tz);
extern struct pg_tm *pg_gmtime(const pg_time_t *timep);
extern int pg_next_dst_boundary(const pg_time_t *timep,
long int *before_gmtoff,
int *before_isdst,
pg_time_t *boundary,
long int *after_gmtoff,
int *after_isdst,
const pg_tz *tz);
extern bool pg_interpret_timezone_abbrev(const char *abbrev,
const pg_time_t *timep,
long int *gmtoff,
int *isdst,
const pg_tz *tz);
extern bool pg_get_timezone_offset(const pg_tz *tz, long int *gmtoff);
extern const char *pg_get_timezone_name(pg_tz *tz);
extern bool pg_tz_acceptable(pg_tz *tz);
/* these functions are in strftime.c */
extern size_t pg_strftime(char *s, size_t max, const char *format,
const struct pg_tm *tm);
/* these functions and variables are in pgtz.c */
extern PGDLLIMPORT pg_tz *session_timezone;
extern PGDLLIMPORT pg_tz *log_timezone;
extern void pg_timezone_initialize(void);
extern pg_tz *pg_tzset(const char *tzname);
extern pg_tz *pg_tzset_offset(long gmtoffset);
extern pg_tzenum *pg_tzenumerate_start(void);
extern pg_tz *pg_tzenumerate_next(pg_tzenum *dir);
extern void pg_tzenumerate_end(pg_tzenum *dir);
#endif /* _PGTIME_H */